Dendrobranchiata

Penaeus monodon

The Dendrobranchiata form a suborder of the decapods. It includes about 500 species, including some economically important farmed shrimp.

Description

As with all decapods laterally flattened body is divided into two tagmata cephalothorax and abdomen. The carapace covering the cephalothorax is an important distinguishing feature of the families within the Dendrobranchiata. So has about the carapace in the family of Solenoceridae a unique in this suborder spike just behind the stalked eyes. Front ends of the carapace in the so-called rostrum, which may have highly variable lengths within this suborder.

The abdomen is longer, or about as long as the cephalothorax in most cases. The pleura ( lateral extensions ) of the second segment ( Somits ) do not overlap those of the first. This distinguishes the types of Dendrobranchiata of the shrimps of the Caridea.

The Dendrobranchiata have scissors on the first three walking legs ( pereiopods ). Exopoditen missing ( Sicyoniidae, Sergestidae, Luciferidae ), are reduced ( Hymenopenaeus sp.), Or missing. The swimming legs ( pleopods ) are eingliedrig in the family of Sicyoniidae, in the remaining families of two elements. The rearmost, shaped to uropods swimming leg pair has no Diaeresis unlike many other decapods.

Characteristic of the Dendrobranchiata are the eponymous gills, which are branched like a tree ( Greek " dendro " tree, " branchia " gills).

Reproduction and life cycle

Copulation usually takes place after a molt of the female, at night or at sunset. Courtship and mating can last up to three hours. Spawning also takes place at night, once in a molting cycle or more times. With the exception of the females Luciferidae operate no parental care, the eggs are dropped directly.

Already in the first 24 hours hatch the nauplii, which are afloat in contrast to the sister group of the Pleocyemata. You can not eat and run through in 68 hours 5-8 nauplius stages. This end when the first two maxillipeds and a carapace are developed and the telson is bipartite. Over the next 5 to 6 zoea stages, the larva eventually developed into the so-called post - larva, which first travels through mold legs. By this stage, the scissors on the first three pairs of legs are functional for the first time. About a few more molts adolescence is reached.

Distribution and habitat

Spread the Dendrobranchiata worldwide at depths of 200 to 2000 meters; mostly between latitudes 40 ° N and 40 ° S. Some types of Sergestidae live in fresh water.

With the exception of planktonic Luciferidae are the Dendrobranchiata creatures of the benthos. They feed omnivorous itself. For example, arrow worms, ostracods, copepods, various molluscs and detritus are eaten.

System

The Dendrobranchiata be divided into two superfamilies and seven extant families:

  • Penaeoidea Rafinesque, 1815 Aristeidae Wood - Mason & Alcock, 1891
  • Benthesicymidae Wood - Mason & Alcock, 1891
  • Sicyoniidae Ortmann, 1898
  • Solenoceridae Wood - Mason & Alcock, 1891
  • Luciferidae De Haan, 1849
  • Sergestidae Dana, 1852

Swell

  • Carolina Tavares and Joel W. Martin: suborder Dendrobranchiata Bate, 1888, In: . FR Schram, JC von Vaupel Klein, J. Forest and M. Charmantier - Daures (ed.): Eucarida: Euphausiacea, Amphionidacea, and Decapoda ( partim). Treatise on Zoology - Anatomy, Taxonomy, Biology - The Crustacea. 9A, Brill Publishers, 2010, ISBN 9789004164413, pp. 99-164 (pdf 2,04 Mb, accessed on 18 February 2012).
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